Varel V H, Yen J T, Kreikemeier K K
Roman L. Hruska U.S. Meat Animal Research Center, USDA Agricultural Research Service, Clay Center, Nebraska 68933.
Appl Environ Microbiol. 1995 Mar;61(3):1116-9. doi: 10.1128/aem.61.3.1116-1119.1995.
Studies were conducted to determine whether intestinal cellulolytic bacteria could be introduced into the bovine rumen or pig large intestine. In the first study, the ruminal fluid of three cows was evacuated and replaced with 20 liters of buffer and 6 liters of the ruminal or swine cellulolytic organism Clostridium longisporum or Clostridium herbivorans, respectively. The introduced organisms were the predominant cellulolytic bacterium in the fluid (> 10(7) cells ml-1) at 0 h. C. longisporum was still the predominant cellulolytic organism after 5 h, at 0.55 x 10(7) cells ml-1; however, after 24 h the count of C. longisporum decreased to 0.05 x 10(7) cells ml-1 compared with 2.8 x 10(7) cells ml-1 for the total cellulolytic organisms. After 48 h, C. longisporum was no longer detectable. C. herbivorans was identified in only one of the three cows after 24 h and was not detected at 72 h. In a second study, when C. longisporum (50 ml; 10(7) cells ml-1) was infused into the terminal ileum of seven pigs, it was not recovered when fecal samples were evaluated at 24, 48, or 72 h after infusion. These studies emphasize the competition that must be overcome to successfully introduce organisms into an intestinal ecosystem. Furthermore, these studies suggest that C. longisporum is a transient organism in the bovine rumen; however, C. herbivorans is part of the normal intestinal flora of some pigs, although the role that it plays in fiber degradation in these pigs is unclear.
开展了多项研究以确定肠道纤维素分解菌能否被引入牛的瘤胃或猪的大肠。在第一项研究中，排空三头奶牛的瘤胃液，分别用20升缓冲液和6升瘤胃或猪的纤维素分解菌长孢梭菌或食草梭菌替代。在0小时时，引入的菌是液体中主要的纤维素分解菌（>10⁷个细胞/毫升）。长孢梭菌在5小时后仍是主要的纤维素分解菌，为0.55×10⁷个细胞/毫升；然而，24小时后，长孢梭菌的数量降至0.05×10⁷个细胞/毫升，而总纤维素分解菌的数量为2.8×10⁷个细胞/毫升。48小时后，长孢梭菌不再能被检测到。24小时后，仅在三头奶牛中的一头检测到食草梭菌，72小时时未检测到。在第二项研究中，当将长孢梭菌（50毫升；10⁷个细胞/毫升）注入七头猪的回肠末端时，在注入后24、48或72小时评估粪便样本时未再检测到该菌。这些研究强调了要成功将微生物引入肠道生态系统必须克服的竞争。此外，这些研究表明长孢梭菌在牛瘤胃中是一种短暂存在的微生物；然而，食草梭菌是一些猪正常肠道菌群的一部分，尽管其在这些猪的纤维降解中所起的作用尚不清楚。
